Fluorinated organic compounds are well known and in recent years have gained technical importance in view of their particular chemical and physical properties such as good thermal resistance and resistance to oxidation. They are also in great demand in pharmaceutical chemistry. For these reasons, simple and economical processes have been sought for obtaining these products.
The fluorination processes up to the time of parent application Ser. No. 185,362, now U.S. Pat. No. 3,878,246 used reagents which are highly toxic or not easily obtainable, or which may even require the use of special equipment. They often lead to secondary polymerization and decomposition reactions. In particular, fluorination of carbonyl groups into difluoromethylene groups can be performed by the use of the reagent SF.sub.4 (see U.S. Pat. No. 2,859,245). In addition to the fact that SF.sub.4 is an extremely toxic gas, the process is difficult to perform. In fact, the solid or liquid reagents must be fed into a hastelloy autoclave under an atmosphere of nitrogen; thereafter one must cool to -80.degree. C., sweep the gases, introduce SF.sub.4, react the mixture at the desired temperature (approx. 100.degree. C.) under autogenous pressure, then cool to -80.degree. C. and finally open the autoclave. The products are then separated. Moreover, it should be pointed out that there is a significant loss of the reagent SF.sub.4 the molar excess of which is between 1.5 and 4 or even more.